Benedict Cumberbatch on Creating His ‘Sherlock’ Character: “I’ve got to understand how I became this person”

It’s easy to forget that Benedict Cumberbatch juggles his film career — including starring as Marvel’s Doctor Strange (if reports are to be believed) — with the popular BBC television series Sherlock, in which he stars as a present-day version of master detective Sherlock Holmes. While dozens of actors have portrayed Holmes on screen, when he was cast in the series he told producer Steven Moffat that he was determined to do his own interpretation of the character. In a conversation with NPR, Cumberbatch spoke about finding his interpretation of Holmes.

Cumberbatch reveals that from the start of the first season he was determined to figure out what made Holmes the man he is in order to portray the character. He explains, “Immediately as an actor I wanted to understand who [Sherlock] was, what his parents were. These were questions I asked … I wanted to understand. [Moffat] was just talking about, ‘Can’t this guy just be good at what he does and he’s your age and he looks like you and he’s doing his thing?’ And I went, ‘No, no Steven, there’s a process I’ve got to go through. I’ve got to understand how I became this person.'”

The reason why understanding those details are so important to Cumberbatch is because he believes in grounding his character. He points out, “I can’t just sort of float onto set with a whole bunch of mannerisms and hope it sort of comes off. You have to ground it in some sort of reality, otherwise you get found out as things sort of evolve.”

Another thing that Cumberbatch insisted on was that Holmes have a flaw — which ended up being the detective’s difficulty with connecting with others. Cumberbatch recalls, “And [Moffat] said, ‘But can’t he just be really good? Can’t he just be good at it? Why does he have to have flaw or an Achilles heel?’Because I said, you know, ‘Where’s his weakness?’ Because no human being doesn’t [have one]. And however much [Sherlock] tries to convince himself he’s not human, he is.”